Wisconsin Wolf Population Drops Slightly

After Wisconsin’s inaugural season of wolf hunting and trapping last fall, the state’s wolf population has declined only slightly.

The 2013 Wisconsin wolf count indicates there are a minimum of 809 to 834 wolves in the state, including 215 packs and 15 lone wolves, according to Department of Natural Resources officials. The count compares to the 2012 estimate that ranged from 815 to 880 wolves, including 213 packs and 20 lone wolves.

“The thing people were concerned about was whether the recent hunting and trapping seasons would have a depressing effect on the wolf population, and I don’t see that in the numbers and the number of packs,” said Ken Jonas, DNR area wildlife supervisor at Hayward.

Last fall, hunters and trappers took 117 wolves statewide.

Wildlife officials said all known wolf mortalities for 2012 fell within expected ranges, including 117 from hunting and trapping, 76 from depredation control, 24 from vehicle collisions, 21 from illegal kills, and five from unknown causes.

Howard Goldman, Minnesota state director for the Humane Society of the United States, said the total wolf mortality in Wisconsin is too high.

“It constitutes almost 30 percent of the population,” Goldman said. “Therefore, I’m very concerned that it’s going to cause a significant reduction in the population. The tipping point I’ve heard over and over is 30 percent. Once they hit 30 percent (mortality), there’s a real possibility the population will decline quickly.”

Goldman and the HSUS had testified against holding a wolf season in Wisconsin.

Wolf research in other states has shown that in most cases, a wolf population can be sustained if the human-caused mortality is no higher than 30 percent, said L. David Mech, wolf biologist with the University of Minnesota and the U.S. Geological Survey.

Wisconsin’s 2013 count represents the fourth time since 1985 that no increase was detected in the wolf population from the previous year, DNR officials said. Wolf counts have been conducted in Wisconsin since 1979-1980 when 25 wolves were counted in the state.

“Generally, the wolf population increased at a rate of 20 percent or more in the 1990s, and at a 10 to 12 percent rate in 2000s,” said David MacFarland, DNR carnivore specialist. “Though the recent count suggests that the wolf population has stabilized or showed a slight decline, science suggests that human-caused wolf mortalities must reach close to 30 percent before wolf populations are reduced. The total known human-caused mortalities of wolves in 2012 amounted to 28 percent of the previous winter’s count, but some level of undetected mortality likely occurred.”

The wolf count relies on a combination of radio-telemetry, pilot observations and winter track counts conducted by staff and trained volunteers across wolf range in Wisconsin, McFarland said. The count is conducted at a time when the wolf population is at its lowest point in the annual cycle. The population nearly doubles when pups are born, but mortalities of adults and young bring those numbers down by the following winter.

The state’s wolf management objectives for 2012 were to ensure a sustainable wolf population and to begin to reduce the wolf population through depredation control, hunting and trapping.

The Wolf Advisory Committee, a diverse group representing DNR, hunting and non-hunting interests, will meet May 23 to develop 2013 wolf quota recommendations.